Michael Bay's first live-action Transformers movie, which launched a continually growing mega franchise in 2007, made a point to emphasize just how lethal and advanced Cybertronians (the "Transformers") are versus measly human technology. In a Qatar desert skirmish against Scorponok, military forces couldn't do much to damage the violent beast with conventional weapons.

It wasn't until an AC-130 gunship entered the fray that the military discovered that high-heat sabot rounds could burn through a Transformer's metal skin. Was it really that easy though? Did Earth forces quickly find out how to effectively kill the alien invaders? Not really.

Continuity isn't a strong point among the four Transformers movies. Even in the first movie, friendly Autobot Bumblebee had his damaged voice box repaired only to never speak again in the following movies, and now he's even getting a spinoff. In that same film, Bumblebee's Nemesis Barricade (the cop car chasing Shia LaBeouf's Sam Witwicky) simply vanished during a chase sequence only to be described as being dead and not-dead in conflicting comics but even he's coming back for Transformers: The Last Knight.

Optimus Prime Explosion

Of course, in the films since, we've seen many Autobots and Decepticons (and other alien units) eliminate each other for good. And by the time Transformers: Dark of the Moon came around, the military was even effective at it as well. So it is possible even if they can occasionally be resurrected.

While visiting the set of Transformers: The Last Knight earlier this year, our own Ben Kendrick had a chance to chat with Harry Humphries - a former United States Navy SEAL who currently works as a consultant and actor on movies - and he helped explain what it would take to actually kill a transformer if they ever invaded our world.

If Transformers invaded tomorrow, what would be the most effective weapons to use against them?

Harry Humphries: We have 40mm weapons that are like that and strategically placed they could - with explosives on the inside - they could take out a limb - a joint, if you will, not a limb - a visual perception capability, etc. because they’re after all machines you know? So you can take a machine out. You can take a machine out with a .50 bullet because of the internals, and the electronics, and the hydraulics that go to making those things work. It’s not that they’re a flesh monster; they’re machines. So that makes them vulnerable. We try to use as large a caliber weapon as we can, so it at least looks believable.

In the first movie they use Sabot rounds. That was the only effective weapon against them. Is that still the case now or has that evolved?

Harry Humphries: Well we’ve through the years discovered that many other weapons can do damage to these guys. The sabot round was developed right after we had the freeze guns, which was in Transformers 1. Freeze guns made sense. Around the writers’ table [they thought] the only way to stop these things is to freeze them.

Of course, a "freeze gun" wasn't actually seen on screen but Megatron was introduced in stasis - held unconscious by freezing. Humphries continues, "so that didn’t work for us as well as maybe just trying to find some legitimate ordinance."

"And a sabot round is basically a round that’s fired from the 105mm cannon, out of a tank. It’s an oversized jacket that fits around a bullet and when it blows out of the gun, the jacket falls off and now you’ve got this bullet that continues its path. And that was a thought that the army came up with, 'Let’s try sabot rounds.' Okay, sabot rounds it was. So we realized that, you know what, these other guns work too. And after all, a sabot round is a bullet. It’s a big bullet but it’s a bullet. So we’ve resolved to making it as large a caliber legitimate weapon as possible and it makes a lot of sense."

Are the Transformers to easily destroyed in the movies (RIP Iron Hide and Ratchet and Jazz)? Share your thoughts in the comments!

Next: How About An R-Rated Bumblebee Movie?

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